Flow diffuser for an exhaust system

ABSTRACT

Exemplary embodiments of the present invention provide devices, systems and methods for distribution of an engine exhaust gas to one or more exhaust treatment devices. In one embodiment, an exhaust flow diffuser is provided including a conduit defining an inlet opening, an outlet opening and a flow path therebetween. The conduit includes a first section disposed proximate to the inlet opening and a second section disposed proximate to the outlet opening. The second section has an increasing diameter along its length. The conduit is formed by a first member and a second member both of which extend between the inlet opening and outlet opening to form a portion of the first section and the second section. The first member and the second member each include an engagement feature that extends between the inlet opening and outlet opening.

FIELD OF THE INVENTION

In accordance with the teachings of the present invention, devices,systems and methods for distribution of an engine exhaust gas to one ormore exhaust gas treatment devices are provided.

BACKGROUND

Exhaust systems of internal combustion engines, particularly vehicleengines, often include one or more exhaust gas treatment devices forreducing the amount of regulated constituents within the exhaust gas.Such treatment systems may include a selective catalytic reduction (SCR)device, diesel particulate filter (DPF), diesel oxidation converter(DOC) or otherwise. Prior to the exhaust gas flowing into an exhaust gastreatment device, the exhaust gas may be pre-treated with urea solution,hydrocarbon fuel or otherwise for improving efficiency of the device.One challenge with these devices is in the even distribution of exhaustgas and fluid additives to the exhaust treatment device while stillconforming to the space constraints for locating the device beneath avehicle. Often, due to the natural flow of the exhaust gas, the exhaustgas is directed towards a center portion of the exhaust gas treatmentdevice or other particular location. This results in a buildup ofcontaminants (e.g., particulate matter or otherwise) on a particularlocation of the exhaust treatment device which requires additionalregenerative heating for removal of such buildup. In other words, priortreatment systems doe not efficiently use the entire device forconversion or treatment. Accordingly, there is a need for a device,system and method for providing even distribution of exhaust gas, andadditives thereof, to an exhaust gas treatment device given a particularspace constraint.

SUMMARY OF THE INVENTION

The present invention provide devices, systems and methods fordistribution of an engine exhaust gas to one or more exhaust gastreatment devices. In one particular configuration, an exhaust flowdiffuser for an exhaust system is provided. The diffuser includes aconduit defining an inlet opening, an outlet opening and a flow paththerebetween. The conduit includes a first section disposed proximate tothe inlet opening and a second section disposed proximate to the outletopening. The second section has an increasing diameter along its lengthand the outlet opening includes a diameter that is larger than adiameter of the inlet opening. The conduit is formed by a first memberextending between the inlet opening and outlet opening to form a portionof the first section and the second section, the first member includinga first engagement feature extending between the inlet opening andoutlet opening. The conduit is also formed by a second member extendingbetween the inlet opening and outlet opening to form a portion of thefirst section and second section, the second member including a secondengagement feature extending between the inlet opening and outletopening. The first and second engagement feature being configured tomatingly engage with each other to join the first and second member andto form the flow path.

In another configuration, an exhaust system for an internal combustionengine is provided. The exhaust system includes an exhaust conduit influid communication with the internal combustion engine to receive andguide an exhaust gas. The system also includes an exhaust gas treatmentdevice for treatment of the exhaust gas. The system further includes adiffuser located between and in fluid communication with the exhaustconduit and the exhaust gas treatment device. The diffuser includes aconduit defining an inlet opening, an outlet opening and a flow paththerebetween. The conduit includes a first section disposed proximate tothe inlet opening and a second section disposed proximate to the outletopening. The second section has an increasing diameter along its lengthand the outlet opening includes a diameter larger than a diameter of theinlet opening. The conduit is formed by a first member extending betweenthe inlet opening and outlet opening to form a portion of the firstsection and the second section, the first member including a firstengagement feature extending between the inlet opening and outletopening. The conduit is also formed by a second member extending betweenthe inlet opening and outlet opening to form a portion of the firstsection and second section, the second member including a secondengagement feature extending between the inlet opening and outletopening, the first and second engagement feature being configured tomatingly engage with each other to join the first and second member andto form the flow path. The conduit further includes a fluid injectorlocated between the internal combustion engine and the exhaust gastreatment device, the fluid injector providing injections of ureasolution or combustible fuel into the exhaust gas.

In still another configuration, a method of disbursing exhaust gas forman internal combustion engine to an exhaust gas treatment device isprovided. The method comprising: flowing exhaust gas through a diffuserthat is fluidly coupled with and disposed between the internalcombustion engine and the exhaust gas treatment device, the diffuserbeing formed of a first member having a first mating surface and asecond member having a second mating surface, the first and secondmembers being joinable to form an inlet opening, an outlet opening and afluid flow path therebetween, diffuser defining a first section disposedproximate to the inlet opening and a second section disposed proximateto the outlet opening, the second section having a gradually increasingdiameter along its length; and injecting urea solution into the exhaustgas prior to or during flow of the exhaust gas through the diffuser.

The above-described and other features and advantages of the exemplaryembodiments of the present invention will be appreciated and understoodby those skilled in the art from the following detailed description,drawings, and appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects, features, advantages and details of the present inventionappear, by way of example only, in the following detailed description ofthe exemplary embodiments, the detailed description referring to thedrawings in which:

FIG. 1 illustrates a perspective view of an exhaust system of a vehicleaccording to an exemplary embodiment of the present invention;

FIG. 2 illustrates a perspective view of an exhaust gas diffuser influid communication with an exhaust gas treatment device according to anexemplary embodiment of the present invention;

FIG. 3 illustrates a perspective view of another exhaust gas diffuser influid communication with an exhaust gas conduit according to anexemplary embodiment of the present invention;

FIG. 4 illustrates a perspective view of another exhaust gas diffuser influid communication with an exhaust gas conduit according to anexemplary embodiment of the present invention;

FIG. 5 illustrates a bottom view of the exhaust gas diffuser shown inFIG. 4;

FIG. 6 illustrates a perspective view of another exhaust gas diffuserpositioned over a frame member of a vehicle assembly according to anexemplary embodiment of the present invention;

FIG. 7 illustrates a perspective view of another exhaust gas diffuser influid communication with an exhaust gas treatment device according to anexemplary embodiment of the present invention;

FIG. 8 illustrates an elevational view of another exhaust gas diffuserin fluid communication with an exhaust treatment device according to anexemplary embodiment of the present invention;

FIG. 9 illustrates a cross-sectional view of the diffuser shown in FIG.3;

FIG. 10 illustrates an alternate configuration of the diffuser shown inFIG. 9;

FIG. 11 illustrates an alternate configuration of the diffuser shown inFIG. 9;

FIG. 12 illustrates a first end view of the diffuser shown in FIG. 6;

FIG. 13 illustrates a second end view of the diffuser shown in FIG. 6;

FIGS. 14 through 25 illustrate elevational and cross-sectional views ofdifferent exhaust gas diffuser configurations according to exemplaryembodiments of the present invention;

FIG. 26 illustrates a side view of a divider according to an exemplaryembodiment of the present invention;

FIG. 27 illustrates a top view of another divider according to anexemplary embodiment of the present invention;

FIG. 28 illustrates an end view of yet another divider according to anexemplary embodiment of the present invention;

FIG. 29 illustrates a perspective view of an exhaust gas flow partitionaccording to an exemplary embodiment of the present invention;

FIG. 30 illustrates a perspective view of an exhaust gas mixing deviceaccording to an exemplary embodiment of the present invention;

FIG. 31 illustrates a perspective view of an exhaust gas swirl deviceaccording to an exemplary embodiment of the present invention;

FIGS. 32 and 33 illustrate two fluid flow profiles through a conduitaccording to the teachings of the present invention; and

FIGS. 34 through 37 illustrate different engine exhaust systemsaccording to exemplary embodiments of the present invention.

DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

The present invention provides devices, systems and methods for evendistribution of exhaust gas from an engine to one or more exhausttreatment devices, such as a selective catalytic reduction (SCR) device,diesel oxidation converter (DOC), diesel particulate filter (DPF) orotherwise. Through this distribution, contaminants of exhaust gas, suchas nitrogen oxides, hydrocarbons, particulate matter or otherwise, areevenly distributed across an inlet of the exhaust gas treatment device.This is particularly advantageous in a DPF as regeneration time forremoval of contaminants collected across the exhaust gas treatmentdevice may be reduced due to the reduction or elimination of localizedbuildup. Further, the even distribution of exhaust gas also reduces hotspots, which may affect durability, formed across the exhaust treatmentdevice due to this localized build up.

Through the features of the present invention, fluid flow velocity andprofile into and out of the exhaust gas treatment device will beimproved, without deleterious effect to the fluid flow velocity. Theimproved fluid flow profile and velocity allows for optimized packagingof the exhaust gas treatment device and potentially reduces thesubstrate volume required for treatment of the exhaust gas. Thisreduction improves durability of the exhaust treatment device andpotentially reduces cost of the overall engine exhaust system. Thefeatures of the present invention are particularly advantageous incertain vehicle configurations where packaging and design constraintsare limiting. For example, through the shape configurations of theinvention, e.g., diffuser or otherwise, it is possible to traversecertain vehicle components, without deleterious effects, such as framemembers and more particularly laterally extending frame members as withladder frame construction. These shapes allow fluid flow throughrelatively narrow spaces while avoiding excessive back pressure withinthe exhaust system while still providing even disbursement of exhaustgas to an exhaust gas treatment device and allowing for improvedpackaging.

In one configuration, even distribution of the exhaust gas is achievedthrough a shaped configuration of a fluid flow diffuser disposed betweenthe engine and the exhaust treatment device. In another configuration,even distribution of the exhaust gas is achieved through strategicplacement of an injector between the engine and the exhaust treatmentdevice. In still another configuration, even distribution of the exhaustgas is achieved through placement of a flow divider of the presentinvention between the engine and the exhaust gas treatment device. Instill other configurations, combinations of these or other features arecontemplated, as shown and described herein, for causing evendistribution of exhaust gas to an exhaust gas treatment device. Throughthese and other features of the present invention, it is possible toevenly disburse the flow of exhaust gas and fluid additives (e.g., ureasolution, combustion fuel or otherwise) through a cross-sectional areaof an inlet of an exhaust gas treatment device. For example, referringto FIG. 32, typical laminar flow of fluid through a pipe-like conduit200 provides a fluid flow profile 202 with a larger volume of theexhaust gas and fluid additive traveling generally through a centerportion of the pipe-like conduit 200. In one embodiment, referring toFIG. 33, the fluid flow profile 202 of the present invention includes amore dispersed fluid flow wherein the volume of the fluid travelingthrough the pipe-like conduit 200 is more evenly disbursed.

Referring to the embodiments shown in FIGS. 1, 3 and 7, a vehicle frameassembly 10 is shown providing support to an engine 12 and engineexhaust system 14. The engine exhaust system 14 includes a diffuser 16for use with an exhaust treatment system 18 for providing disbursementof exhaust gas to an exhaust treatment device 20. The diffuser 16includes a conduit 22 defining a cavity 24. The cavity is in fluidcommunication with an inlet opening 26 and an outlet opening 28 forforming a fluid flow path through the diffuser 16. In one configuration,the conduit includes one or more features for assisting in thedisbursement of exhaust gas through the conduit 22. For example, thefeature may comprise a divider 30 for forming one or moresub-passageways through the diffuser. In another configuration, thediffuser 16, exhaust treatment system 18 or exhaust system of the engine14 includes an injector assembly 32, including an injector mount 34 andinjector 36, for injection of urea solution or hydrocarbon fuel into theexhaust gas flowing through the diffuser 16. In still anotherconfiguration, the diffuser 16 is shaped to cause expansion anddisbursement of the exhaust gas flowing from the inlet opening 26 to theoutlet opening 28 of the diffuser 16.

Referring to FIG. 3, a first engagement feature 38 is provided forcoupling the diffuser 16 to an exhaust component, such as an exhaustconduit 40, exhaust pre-treatment device (not shown) or otherwise.Similarly, a second engagement feature 44 is provided for coupling thediffuser 16 to an exhaust treatment device 20, such as an SCR, DOC, DOCor otherwise. The first and second engagement feature may comprise anysuitable engagement feature such as a flange, lip, groove or otherwise.Further, engagement between diffuser 16 and the corresponding exhaustcomponents may be maintained through any suitable attachment featuresuch as a weld, adhesive, mechanical fastener, combinations thereof orother suitable attachment.

Referring to FIGS. 12 and 13, the size and shape of inlet opening 26 andoutlet opening 28 may comprise any suitable size and shape thatcorrespond to an opening of the exhaust component, which they engage. Inone configuration, the outlet opening 28 is larger than the inletopening 26. For example, it is contemplated that the outlet opening mayinclude at least one interior diameter “d_(o)” that is at least about1.25% larger than an interior diameter of the inlet opening “d_(i)”, oreven at least about 1.5% larger than an interior diameter of the inletopening “d_(i)” or even 2.0% larger than an interior diameter of inletopening “d_(i)”. Similarly, it is contemplated that the outlet openingcross-sectional area “a_(o)” that is at least about 1.25% larger than across-sectional area of the inlet opening “a_(i)”, or even at leastabout 1.5% larger than a cross-sectional area of the inlet opening“a_(i)” or even 2.0% larger than a cross-sectional area of inlet opening“a_(i)”. Other configurations are possible.

The shape of inlet opening 26 and outlet opening 28 may be similar ordissimilar and may include any suitable shape such as circular, oval,elliptical, square, rectangular or otherwise. The diameter of the inletopening “d_(i)” and the outlet opening “d_(o)” may include any suitablediameter size. For example, the inlet opening 26 may include a diameter“di” that is between about 2-4 inches and more particularly in oneexemplary embodiment about 3 inches. The outlet opening 28 may include adiameter “do” that is between about 6-10 inches, and more particularlyin one exemplary embodiment 7 inches by 9 inches. In one embodiment,referring to FIGS. 6, 12 and 13, the inlet opening 26 includes acircular cross-sectional shape and the outlet opening 28 includes anoval cross-sectional shape. In this embodiment, the inlet openingincludes a diameter “di” of about 3 inches and the outlet openingincludes a width diameter “w-do” of about 9 inches and a height diameter“h-do” of about 7 inches. However, these are non-limiting dimensions asother dimensions are available including greater or less than the abovereferenced dimensions.

Similarly, the conduit 22 may include any suitable size or shape forfluidly connecting the inlet opening 26 and the outlet opening 28, whichmay include any of the sizes of the inlet opening and outlet opening. Inone embodiment, as shown in FIG. 2 and 4-6, the conduit 22 is shaped totraverse about one or more frame members 46 of the vehicle frameassembly 10. In this embodiment, it is contemplated that the shape ofthe conduit may include a portion that is non-circular in shape, such aselliptical, oval or otherwise, for placement and maintaining fluid flowvelocity about one or more vehicle frame members 46. Through thesenon-circular configurations, e.g., flattening, widening and/or narrowingcertain portions of the conduit 22, it is possible to maintain fluidflow velocity between the inlet opening 26 and outlet opening 28,without excessive exhaust gas backpressure. Also, the conduit 22 may beconfigured to cause or maintain even disbursement of exhaust gases andparticulate matter flowing through the conduit. The disbursement ofexhaust gas may be achieved, at least in part, through one or moresections of the conduit 22 being formed with contours for causinggradual expansion of the gas between the inlet opening 26 and the outletopening 28. For example, such contours may comprise shapes (cylindrical,frustroconcial or otherwise), twists, bends or other contours.

Referring to FIGS. 14-25, the contour of the conduit 22 may include anon-circular portion such as an elliptical or oval cross-sectionalportion, or otherwise, extending along a length “l” of the length “L” ofthe conduit. This non-circular portion may comprise a widening ornarrowing of the width, height, or otherwise of the conduit 22. Thenon-circular portion may be located towards the inlet opening 26, outletopening 28, or in a center portion 88 of the conduit. The non-circularportion may include a substantially consistent cross-sectional areaalong a length of the conduit, variable cross-sectional area along alength of the conduit, increasing and/or decreasing cross-sectional areaalong a length of the conduit or otherwise. The non-circular portion mayextend over all or a portion of the length of the conduit 22. Forexample, the non-circular portion may include a length “l” that extendsover at least about ¼ of the length “L” of the conduit, at least about ½of the length of the conduit, at least about ¾ of the length of theconduit or otherwise. Further, the non-circular portion may include alength “l” that extends over a substantial length “L” of the conduit.Other configurations are possible.

Further, with respect to elliptical type non-circular portions, thedegree of the elliptical shape of conduit 22 may vary along the length“l” of the non-circular portion. For example, the elliptical shape maybegin just below about 90° and gradually decrease to at least 85°, 80°,75°, 70°, 60° or less. Subsequently, the degree of the elliptical shapemay increase back up to 70°, 75°, 80°, 85° or even just below about 90°.It is contemplated that the degree of the non-circular ellipticalportion may change by as much as at least about 5°, 10°, 15°, 30° ormore. Similarly, a ratio of width to height of a cross sectional area ofthe non-elliptical portion may be at least about 1.25:1, 1.5:1, 1.75:1,2:1 3:1 or more. As with the degree of the non-circular portion, theratio may change over a length of the non-circular portion including agradual increasing or decreasing change from a first end of thenon-circular portion to a second end of the non-circular portion. Otherconfigurations are possible.

As shown in the drawings, the conduit 22 is formed of a first section 48having a first cross-sectional area and a second section 50 having asecond cross-sectional area, wherein the first section is locatedproximate to the fluid inlet opening 26 and the second section islocated proximate to the fluid outlet opening 28. In this configuration,the second section 50 includes an inner diameter larger than an innerdiameter of the first section 48 for providing expansion of the exhaustgas as it flows through the conduit 22. For example, referring to theexemplary configurations shown in FIGS. 3 and 6, the conduit 22 mayinclude a cylindrical first section 48 and a frustroconical secondsection 50 indirectly connected together through a third section 52,comprising an elbow or otherwise. In another configuration, referring toFIG. 8, the conduit may include a frustoconical first section 48 and afrustoconical second section 50 directly connected together. In theseconfigurations, as gas exits the first section 48 and enters the secondsection 50 the gas is diffused and expands outwardly as it flows throughthe conduit 22. It should be appreciated that the conduit may includeother sections, such as end sections 54 or otherwise, which may includeany of the shape and size configurations described herein (e.g.,circular or non-circular).

The diffuser 16 may be formed using any suitable material and formingtechnique common for forming exhaust components. For example, suitablematerials include metal, metal alloys, ceramic or combinations thereof.Also, suitable forming techniques include molding, stamping, extrudingtechniques or otherwise. In one configuration, the diffuser 16 iscomposed of metal and formed, at least in part, through a stampingprocess. In this configuration, the diffuser 16 is formed as a two partmember with corresponding mating structures for joining the components.More specifically, as shown in FIGS. 6, 12 and 13, the diffuser isformed of a first diffuser member 56 having a first mating structure 58and a second diffuser member 60 having a second mating structure 62. Thefirst and second mating structures 58, 62 are configured to be joinedtogether to form a diffuser joint 64. Examples of joints that may beformed through the first and second mating structures include lap joint,tongue and groove joint or otherwise. This clam-shell configurationallows the first and second diffuser members 56, 60 to be broughttogether, aligned and attached through a suitable attachment means suchas adhesive bonding, welding, mechanical fastening or otherwise. Thisclam-shell configuration is particularly advantageous as it allows foradditional components, such as a divider 30, flow partition 124, mixingdevice 132, swirl device 140 or otherwise, to be placed within thediffuser for causing mixing or disbursement of the exhaust gasthroughout the cross-sectional area of the diffuser.

In one configuration, the diffuser 16 includes a divider 30 extendingthrough at least a portion of the conduit 22 and between inlet opening26 and outlet opening 28. The divider 30 is configured to separate ormaintain separation of the exhaust gas flowing through diffuser 16. Thedivider 30 is also configured to assist in the evaporation of injectedfluids through the elevated temperature of the divider and/or impact ofthe injected fluid with the divider. For example, referring to theconfigurations of FIGS. 3, 7 and 9, the divider 30 separates the flow ofexhaust gas through conduit 22 into a first sub-passageway 66 and asecond sub-passageway 68. The first and second sub-passageways maygenerally have equal cross-sectional areas or may be proportionatelydivided. In another configuration, referring to FIG. 10, it is alsocontemplated that the divider 30 may be configured to form a firstsub-passageway 70, a second sub-passageway 72 and a third sub-passageway74, wherein the first, second and third sub-passageways include agenerally equal cross-sectional areas. Also, referring to FIG. 11, it isfurther contemplated that the divider 30 may be configured to form afirst sub-passageway 76, a second sub-passageway 78, a thirdsub-passageway 80 and a fourth sub-passageway 82, wherein the first,second, third and fourth sub-passageways include generally equalcross-sectional areas. Other configurations are possible includingadditional sub-passageways, different shaped sub-passageways, differentproportions of cross-sectional areas or otherwise.

The divider 30 is suitable in length to assist in limiting or preventingthe migrating or congregation of exhaust gas towards a central axis “A”of the conduit 22. For example, it is contemplated that divider 30 mayextend at least about 50% of the length of the conduit, at least about60% of the conduit, at least about 75% of the conduit, at least about85% of the conduit or more. In one configuration, the divider 30includes a first end 84 located proximate to the inlet opening 26 and asecond end 86 which is located in a central portion 88 of the conduit.However, in an alternate configuration, the second end 86 of the divider30 may extend to the outlet opening 28. Also, the second end 86 of thedivider 30 may be located proximate to the outlet opening 28 and thefirst end 84 is located in a central portion 88 of the conduit 22. Otherconfigurations are possible.

Referring to the embodiments shown in FIGS. 3, 7 and 9, the divider 30includes a first side 90 having a first surface area and a second side92 having a second surface area. The first and second sides act incombination with interior walls of the conduit 109 to form the first andsecond sub-passageway 66, 68. Similarly, referring to FIG. 10, thedivider 30 may comprise a first arm 94, a second arm 96 and a third arm98 extending from a central portion of the divider 30 and along the axisA of the conduit. In this configuration, each arm includes a first andsecond surface which in combination with the interior walls 109 of theconduit forms a first, second and third sub-passageway 70, 72, 74. Instill another embodiment, referring to FIG. 11, the divider may comprisea first arm 100, a second arm 102, third arm 104 and a fourth arm 106,which forms the first, second, third and fourth sub-passageway 76, 78,80, 82.

In any of the above referenced embodiments, it is contemplated that thedivider 30 includes one or more peripheral edge 108 extending along thedivider. For example, as shown in FIGS. 9-11, the peripheral edges havea corresponding shape to at least a portion of the interior walls 109 ofthe conduit 16 for attachment of the divider 30 to the conduit andmaintaining separation of exhaust between the sub-passageways.Accordingly, the diameter or shape of the divider 30 may include any ofthe diameters or shapes of the conduit 22, particularly thecross-sectional areas of the first section 48, second section 50 orthird section 52, as shown in FIG. 6. As such, it is contemplated thatthe divider 30 may include a continuously increasing or decreasing widthor may include one or more changes in contour. Also, it is contemplatedthat the divider 30 may include one or more contours along its length.For example, referring to the embodiments shown in FIGS. 26-28, thedivider may include one or more flat portions 110, one or more bends 112(e.g., traverse or vertical bend with respect to the divider length),and one or more twists 114.

Optionally, as shown in FIG. 3, the divider 30 may include one or more,a plurality or even an array of perforations or openings 116 formedalong a length and width of the divider and extending through thedivider. However, as shown in FIGS. 6, 7 and 9, the divider 30 maycomprise a continuous member substantially free of perforations oropenings formed therethough. The openings 116, as shown in FIG. 3, allowfor fluid communication between the first and second sub-passageways 72,74. However, with reference to the divider configurations shown in FIGS.10 and 11, the openings may further allow fluid communication betweenmore than two sub-passageways. These configurations are particularlyadvantageous when used in conjunction with an injector assembly 32providing a spray pattern that intersects at least some of the openings116 formed through the divider 30. These openings 116 are furtheradvantageous as they not only allow for mixing of exhaust gases flowingthrough the conduit 22 but also provide mixing of an injected fluid(e.g., urea solution, hydrocarbon fuel or otherwise) with the exhaustgas. In the exemplary embodiment shown in FIG. 3, this is achieved byallowing a first portion of the injected fluid to pass through theopenings 116 and mix with the exhaust gas below the divider 30 and asecond portion of the injected fluid impacts the divider or otherwisemixes with the exhaust fluid flowing above the divider. In one exemplaryembodiment, with continued reference to FIG. 3, the summation of theopen areas of openings 116 within a spray pattern of the fluid injector36 is generally equal to the summation of the surface area of thedivider 30 within the spray pattern of the fluid injector. This allowsfor roughly half of the fluid injected from the fluid injector 36 totravel to the second sub-passageway 68 while the other half remainswithin the first sub-passageway 66. These openings 116 may extend overat least about ¼ of the length of the divider 30, at least about ½ ofthe length of the divider, at least about ¾ of the length of the divideror otherwise. Further, these openings may extend over at least about ¼of the width of the divider, at least about ½ of the width of thedivider, at least about ¾ of the width of the divider or otherwise.

The divider 30 may be formed using any suitable material and formingtechniques common for forming exhaust components, or the conduitdescribed herein. For example, suitable materials include metal, metalalloys, ceramic or combinations thereof. Also, suitable formingtechniques include molding, stamping, extruding techniques orcombinations thereof. In one configuration, it is contemplated that theperforation openings 116 formed through the divider may be stampedthrough the divider. It should be appreciated that other suitablematerials and forming techniques are possible and within the scope ofthe present invention.

As previously mentioned, the exhaust treatment system 18 may include oneor more injector assemblies 32 for the injection of fluids into anexhaust gas stream for treatment thereof. Such fluids may includehydrocarbon fuels or other combustible fluid such as gas, diesel,alcohol or otherwise. Such fluid may also include ammonia containingfluids such as urea solutions. Other fluids are possible as well. Asshown in FIGS. 3, 4 and 9, the injector assembly may include an injector36 in fluid communication with an exhaust gas flowing through aninjector opening 118 formed through an exhaust conduit 40, diffuser 16,exhaust treatment device 20, exhaust pre-treatment device (not shown) orother conduit for the engine exhaust system 14. Accordingly, theinjector assembly may be formed with or mounted to the diffuser 16,exhaust conduit 40, exhaust treatment device 20 or otherwise. In oneparticular embodiment, one or more injector assemblies 32 are placedupstream from an exhaust treatment device 20. In one configuration, theinjector assembly 32 and injector opening 118 are located proximate to aplurality of openings formed through divider 30. Still further, inanother configuration, the injector assembly is disposed on the firstsection 48 of the diffuser. In still another configuration the injectorassembly is located closer to the engine 12 than the diffuser 16 forallowing thorough mixing of injected fluids. Other configurations areavailable.

In one exemplary embodiment, referring to FIG. 3, the injector 36 ismounted at an angle “α” with respect to the first or second side 90, 92of the divider 30 and is configured to generate a spray pattern thatintersects the divider. Suitable angles include between about 15° to45°, or even between about 20° to 40° or otherwise. Advantageously, incertain configurations, the spray pattern is orientated such that itintersects a portion of openings 116 formed by a perforated divider 30.In this particular configuration, as previously discussed, a certainamount of spray enters the sub-passageway through the openings and acertain amount of spray remains in the sub-passageway in which theinjector opening 118 is located. In another particular configuration,the divider 30 is substantially free of openings 116 formedtherethrough. In this configuration, fluid may be injected on one orboth sides 90, 92 of the divider 30 wherein the injected fluid impactsthe divider and/or interior walls 109 of the conduit 22.

The diffuser 16 may include one or more additional modifiers forcontrolling the flow pattern of exhaust into, through or out of thediffuser. The flow modifiers are configured to cause further mixing ofan injected fluid with the exhaust gas flowing through the diffuser 16.Such flow modifier may be located anywhere throughout the conduit 16including the inlet opening 26, outlet opening 28, or therebetween. Itis also contemplated that the flow modifier may be located outside ofthe conduit 16 such as adjacent the inlet opening 26, outlet opening 28or otherwise.

Referring to FIG. 29, a first exemplary flow modifier is providedcomprising a flow partition 124. In this configuration, the flowpartition is located at an inlet opening 26 of the conduit 22 forcausing mixing and distributing of exhaust gas entering through theinlet opening. The flow partition includes a plurality of vertically andhorizontally extending walls 126 forming an array of openings 128 forcontrolling the flow of exhaust gas entering the inlet. Optionally, theflow partition includes deflectors 130 for deflecting or redirecting theflow of exhaust gas through the openings. Referring to FIG. 30, a secondexemplary flow modifier is provided comprising a mixing device 132. Inthis configuration, the mixing device is located at an inlet opening 26of the conduit 22 for mixing exhaust gas entering through the inletopening. The mixing device includes a base portion 134 and one or moreengagement features 136 located on a periphery of the base portion forengagement with the interior walls 109 of the conduit 22. The mixingdevice 132 further includes one or more angularly extending or flowmodifying tabs 138 extending from the base portions to cause mixing ordeflection of exhaust gas and fluid passing thereby. In oneconfiguration, the tabs extend in a direction which is non-parallel toan axis “A” of the conduit. Referring to FIG. 31, a third exemplary flowmodifier is provided comprising a swirl device 140. In thisconfiguration, the swirl device includes a main body 142 and fins 144extending therefrom to cause rotational movement of exhaust gas passingthereby. The swirl device 140 is located towards a central portion 88,see FIG. 7, of the conduit 22 and extends partially into the secondfrustroconical section 50 of the conduit 22.

Referring to FIGS. 34 through 37, exemplary exhaust treatment systems 18and fluid flow patterns 146 are shown. In a first configuration, asshown in FIG. 34, a diffuser 16 is provided having injector assembly 32for introduction of a fluid such as urea solution, combustible fluid orotherwise. Upon injection, the fluid disburses to form an expanded fluidflow pattern 146. In a second configuration, as shown in FIG. 35, adiffuser 16 is provided having an injector assembly 32 for introductionof a fluid. Upon injection, the fluid disburses to form an expandedfluid flow pattern 146. The pattern is further modified through a swirldevice 140 to form a rotating fluid flow pattern for further mixing anddistribution of the exhaust gas. Referring to FIG. 36, a diffuser 16 isprovided having an injector assembly 32 for introduction of a fluid andfurther includes a divider 30. Upon injection, a portion of the fluidimpacts the divider and travels along a first sub-passageway 66. Anotherportion of the fluid travels through openings 116, formed through thedivider, and impacts an interior wall 109 of the conduit and furthertravels along a second sub-passageway 68, wherein the injected fluidforms an expanded fluid flow pattern 146. Referring to FIG. 37, adiffuser 16 is provided having an injector assembly 32 for introductionof a fluid and further includes a divider 30. Upon injection, a portionof the fluid impacts the divider and travels along a firstsub-passageway 66. Another portion of the fluid travels through openings116, formed through the divider, and impacts an interior wall 109 of theconduit and further travels along a second sub-passageway 68, whereinthe injected fluid forms an expanded fluid flow pattern 146. The patternis further modified through a swirl device 140 to form a rotating fluidflow pattern.

The present invention further provides a method of providingdisbursement of exhaust gas from an engine 12 to an exhaust treatmentsystem 18 is provided. The method includes fluidly coupling a diffuser16 with an exhaust conduit 40 extending from the engine. The diffuser isfurther fluidly coupled to an exhaust treatment device 20, as describedherein. The diffuser includes a conduit 22 defining a flow path betweenan inlet opening 26 and outlet opening 28. The conduit 22 is formed of afirst diffuser member 56 and second diffuser member 60 operable tomatingly join to define a first section 48 defining a cylindrical orfrustroconical shape and a second section 50 defining a frustroconicalshape. In one particular configuration, the method further includesplacing a divider 30 within the conduit 22 for forming a firstsub-passageway 66 and a second sub-passageway 68. In one configuration,the divider includes a plurality of openings 116 for providing fluidflow between the first sub-passageway 66 and the second sub-passageway68. In this particular configuration, the method further includeinjecting a urea solution or combustible fluid into an exhaust gasflowing through the conduit, with injector assembly 32, such that the atleast part of the injected fluid impacts the divider 30.

The diffusers 16, including the associated components, may be used invarious engine applications including diesel engines, gasoline enginesor other internal combustion engines. Such engines may be used invehicle industry, e.g., mass transit vehicles, personal automotivevehicles, trucks or otherwise. The diffuser may also be used innon-vehicle applications such stationary engines used for mechanical orelectrical power generation or otherwise. The diffuser 16 may be used toprovide improved disbursement of exhaust gas, including particulatematter and other combustion gaseous product, to one or more exhausttreatment device 20. Such exhaust treatment devices 20 may compriseselective catalytic reduction device, diesel oxidation catalyst device,diesel particulate filter, diesel particulate traps, closed coupledconverter, catalytic converters or otherwise. In one configuration,referring to FIG. 1, it is contemplated that a single diffuser 16 isused for the engine exhaust system 14 and is connected to a selectivecatalytic reduction device for providing disbursement of exhaust gasthereto. In another configuration, it is also contemplated that multiplediffusers 16 are used to provide disbursement of exhaust gas to morethan one exhaust treatment device 20, as described herein. It is alsocontemplated that a diffuser 16 may be located downstream, e.g.,attached or in fluid communication, with one or more exhaust treatmentdevices 20.

While the invention has been described with reference to exemplaryembodiments, it will be understood by those skilled in the art thatvarious changes may be made and equivalents maybe substituted forelements thereof without departing from the scope of the invention. Inaddition, many modifications may be made to adapt a particular situationor material to the teachings of the invention without departing from theessential scope thereof. Therefore, it is intended that the inventionnot be limited to the particular embodiment disclosed as the best modecontemplated for carrying out this invention, but that the inventionwill include all embodiments falling within the scope of the appendedclaims.

1. An exhaust flow diffuser for an exhaust system, comprising: a conduitdefining an inlet opening, an outlet opening and a flow paththerebetween, the conduit including a first section disposed proximateto the inlet opening and a second section disposed proximate to theoutlet opening, the second section having an increasing diameter alongits length and the outlet opening includes a diameter larger than adiameter of the inlet opening, the conduit being formed by: a firstmember extending between the inlet opening and outlet opening to form aportion of the first section and the second section, the first memberincluding a first engagement feature extending between the inlet openingand outlet opening, a second member extending between the inlet openingand outlet opening to form a portion of the first section and secondsection, the second member including a second engagement featureextending between the inlet opening and outlet opening, and the firstand second engagement feature being configured to matingly engage witheach other to join the first and second members and to form the flowpath.
 2. The diffuser of claim 1, further comprising a divider extendingbetween the inlet opening and the outlet opening, the divider beingconfigured to separate the flow path into a first sub-passageway and asecond sub-passageway.
 3. The diffuser of claim 2, wherein the divideris perforated to form a plurality of openings extending from a firstside of the divider to a second side of the divider.
 4. The diffuser ofclaim 3, wherein the divider includes at least one change in contouralong a length of the divider.
 5. The diffuser of claim 4, wherein thedivider includes a first end located within the first section and asecond end located within the second section.
 6. The diffuser of claim1, wherein the diffuser further includes an injector mount forattachment of a fluid injector.
 7. The diffuser of claim 6, wherein theinjector mount is disposed on the first section of the diffuser.
 8. Thediffuser of claim 7, further comprising a divider extending between theinlet opening and the outlet opening, the divider being configured toseparate the flow path into a first sub-passageway and a secondsub-passageway.
 9. The diffuser of claim 8, wherein the divider isperforated to form a plurality of openings extending between a firstside of the divider to a second side of the divider, the injector mountconfigured to orientate an attached injector towards the plurality ofopenings of the divider.
 10. An exhaust system for an internalcombustion engine, comprising: an exhaust conduit in fluid communicationwith the internal combustion engine to receive and guide an exhaust gas;an exhaust gas treatment device for treatment of the exhaust gas; adiffuser located between and in fluid communication with the exhaustconduit and the exhaust gas treatment device, the diffuser including aconduit defining an inlet opening, an outlet opening and a flow paththerebetween, the conduit including a first section disposed proximateto the inlet opening and a second section disposed proximate to theoutlet opening, the second section having an increasing diameter alongits length and the outlet opening includes a diameter larger than adiameter of the inlet opening, the conduit being formed by: a firstmember extending between the inlet opening and outlet opening to form aportion of the first section and the second section, the first memberincluding a first engagement feature extending between the inlet openingand outlet opening, a second member extending between the inlet openingand outlet opening to form a portion of the first section and secondsection, the second member including a second engagement featureextending between the inlet opening and outlet opening, and the firstand second engagement feature being configured to matingly engage witheach other to join the first and second member and to form the flowpath; and a fluid injector located between the internal combustionengine and the exhaust treatment device, the fluid injector providinginjections of urea solution or combustible fuel into the exhaust gas.11. The exhaust system of claim 10, wherein the fluid injector ismounted to the first section of the diffuser.
 12. The exhaust system ofclaim 10, wherein the fluid injector is mounted to the exhaust conduit.13. The exhaust system of claim 12, wherein the urea injector is locatedcloser to the engine than the diffuser.
 14. The exhaust system of claim10, wherein the diffuser includes a divider extending between the inletopening and outlet opening, the divider being configured to separate theflow path into a first sub-passageway and a second sub-passageway. 15.The exhaust system of claim 14, wherein the divider is perforated andincludes a plurality of openings extending between a first side of thedivider to a second side of the divider.
 16. A method of disbursingexhaust gas form an internal combustion engine to an exhaust gastreatment device, the method comprising: flowing exhaust gas through adiffuser that is fluidly coupled with and between the internalcombustion engine and the exhaust gas treatment device, the diffuserbeing formed of a first member having a first mating surface and asecond member having a second mating surface, the first and secondmembers being joinable to form an inlet opening, an outlet opening and afluid flow path therebetween, diffuser defining a first section disposedproximate to the inlet opening and a second section disposed proximateto the outlet opening, the second section having a gradually increasingdiameter along its length; and injecting urea solution into the exhaustgas prior to or during flow of the exhaust gas through the diffuser. 17.The method of claim 16, wherein an injector is mounted to an exhaustconduit located between the diffuser and the internal combustion enginefor injection of the urea solution into the exhaust gas.
 18. The methodof claim 16, wherein an injector is mounted to the diffuser forinjection of the urea solution into the exhaust gas.
 19. The method ofclaim 16, wherein the diffuser includes a divider extending between theinlet opening and outlet opening, the divider being configured toseparate the flow path into a first sub-passageway and a secondsub-passageway.
 20. The method of claim 19, wherein the divider includesa plurality of openings extending between a first side of the divider toa second side of the divider, the injection of the urea solution beingproximate to the plurality of openings.